Bell 206

Bell 206

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Bell 206

Bell 206 JetRanger
Role	Multipurpose utility helicopter
Manufacturer	Bell Helicopter Textron
First flight	8 December 1962 (206)^[1] 10 January 1966 (206A)^[2]
Introduced	1967
Status	Active service
Primary user	CHC Helicopter
Variants	OH-58 Kiowa Bell 407 Panha Shabaviz 2061

The Bell 206 is a family of two-bladed, single- or twin-engine helicopters, manufactured by Bell Helicopter at its Mirabel, Quebec plant. Originally developed for the United States Army's Light Observation Helicopter program, the 206 failed to be selected. Bell redesigned the airframe and successfully marketed the aircraft commercially as the five-place Bell 206A JetRanger. The new design was eventually selected by the Army as the OH-58 Kiowa. Bell also developed a seven-place LongRanger, which was later offered with a twin-engine option as the TwinRanger, while Tridair Helicopters offers a similar conversion of the LongRanger called the Gemini ST. The ICAO-assigned model designation B06 is used on flight plans for the JetRanger and LongRanger, and the designation B06T is used for the twin-engine TwinRangers.

Development

On 14 October 1960, the United States Navy solicited response from 25 aircraft manufacturers to a request for proposals (RFP) on behalf of the Army for the Light Observation Helicopter (LOH). Bell entered the competition along with 12 other manufacturers, including Hiller Aircraft and Hughes Tool Co., Aircraft Division. Bell submitted the D-250 design, which would be designated as the YHO-4. . On 19 May 1961, Bell and Hiller were announced as winners of the design competition.

YOH-4A LOH in flight

Bell developed the D-250 design into the Model 206 aircraft, redesignated as YOH-4A in 1962, and produced five prototype aircraft for the Army's test and evaluation phase. The first prototype flew on 8 December 1962. The YOH-4A also became known as the Ugly Duckling in comparison to the other contending aircraft. Following a flyoff of the Bell, Hughes and Fairchild-Hiller prototypes, the Hughes OH-6 was selected in May 1965.

When the YOH-4A was eliminated by the Army, Bell went about solving the problem of marketing the aircraft. In addition to the image problem, the helicopter lacked cargo space and only provided cramped quarters for the planned three passengers in the back. The solution was a fuselage redesigned to be more sleek and aesthetic, adding 16 cubic feet (0.45 m) of cargo space in the process. The redesigned aircraft was designated as the Model 206A, and Bell President Edwin J. Ducayet named it the JetRanger denoting an evolution from the popular Model 47J Ranger.

206L LongRanger

The 206L LongRanger is a stretched variant with seating for seven (the LongRanger, stretched a total of 30 inches (760 mm), adds two rear-facing seats in between the front and rear seats). Since their first delivery in 1975, Bell has produced more than 1,700 Ls across all variant types. In 1981 a military version was released, the 206L "TexasRanger". The original 206L utilized a Allison 250-C20B engine, and a series of model upgrades replaced this engine with more powerful versions; the 206L-1 used a 250-C28 and the 206L-3 and 206L-4 used the 250-C30P with 490 shaft horsepower.

In 2007, Bell announced an upgrade program for the 206L-1 and 206L-3 which is designed to modify the aircraft to the 206L-4 configuration; modified aircraft are designated 206L-1+ and 206L-3+. Modifications include strengthened airframe structural components (including a new tailboom), improved transmission, upgraded engine for the L-1, all of which result in a max gross weight increase of 300 pounds and increased performance.

Gemini ST and TwinRanger

The TwinRanger name dates back to the mid-1980s when Bell first developed the Bell 400 TwinRanger, but it never entered production.

In 1989, Tridair Helicopters began developing a twin engine conversion of the LongRanger, the Gemini ST. The prototype's first flight was on 16 January 1991, while full FAA certification was awarded in November. Certification covers the conversion of LongRanger 206L-1s, L-3s and L-4s to Gemini ST configuration. In mid-1994 the Gemini ST was certificated as the first Single/Twin aircraft, allowing it to operate either as a single or twin engine aircraft throughout all phases of flight.

The Bell 206LT TwinRanger was a new build production model equivalent to Tridair's Gemini ST, and was based on the 206L-4. Only 13 206LTs were built, the first being delivered in January 1994, and the last in 1997. The TwinRanger was replaced in Bell's line-up by the mostly-new Bell 427.

Operational history

Bell 206L-4 Long Ranger IV (operated by CTV British Columbia), taking off from Vancouver Harbour helipad.

The first Model 206A flew on 10 January 1966, and the aircraft was revealed later that month at the Helicopter Association of America (HAA) convention. On 20 October 1966, the JetRanger received full certification by the Federal Aviation Administration (FAA) and delivery of the JetRanger to customers began on 13 January 1967, with the first aircraft being purchased by Harry Holly, president of the Hollymatic Company and previous owner of a Bell Ranger.

The Army eventually selected the 206A in 1968 for use as the OH-58 Kiowa. The United States Navy selected the 206A as its primary trainer the TH-57 Sea Ranger, in 1968, and the Army selected the 206B-3 in 1993, to serve as its primary trainer, the TH-67 Creek. The JetRanger is popular with news media for traffic and news reporting. The LongRanger is commonly used as an air ambulance and as a corporate transport.

The basic shape and design of the JetRanger remained unchanged since 1967, but the 206B "JetRanger II" entered the market in 1971 and the 206B-3 "JetRanger III", with its modified tail rotor and more powerful engine, in 1977. The 206 is flown by a single pilot, who sits in the front right seat.

The Bell 206 was the first helicopter to fly around the world and was piloted by Australian Businessman Dick Smith in 1983. During the trip he landed on container ships at sea to refuel.

On 24 January 2008, Bell Helicopter Textron announced plans to terminate production of the Bell 206B-3 model after current order commitments are fulfilled in 2010.

Variants

A Bell 206L-3

Bell 206B-3

Civilian

Bell 206 - Five (5) YOH-4A prototypes, for flight evaluation in the Army's LOH program (1963).
Bell 206A - Initial production version, powered by an Allison 250-C18 turboshaft engine. FAA-certified in 1966. Selected as the OH-58A Kiowa in 1968.
- Agusta-Bell 206A - License-built in Italy
Bell 206A-1 - OH-58A aircraft that are reverse-modified for FAA civil certification.
Agusta-Bell 206A-1 - License-built in Italy
Bell 206B - Upgraded Allison 250-C20 engine.
- Agusta-Bell 206B - License-built in Italy
Bell 206B-2 - Bell 206B models upgraded with Bell 206B-3 improvements.
Bell 206B-3 - Upgraded Allison 250-C20J engine and added 2 inches (51 mm) to tail rotor diameter for yaw control.
Bell 206L LongRanger - Stretched, seven seat configuration, powered by an Allison 250-C20B turboshaft engine.
- Agusta-Bell 206L LongRanger - License-built in Italy
Bell 206L-1 LongRanger II - Higher-powered version, powered by an Allison 250-C28 turboshaft engine.
- Agusta-Bell 206B-1 - License-built in Italy.
Bell 206L-1+ LongRanger - Bell modifications, including 250-C30P engine, to upgrade aircraft to 206L-4 configuration.
Bell 206L-3 LongRanger III - Powered by an Allison 250-C30P turboshaft engine.
- Agusta-Bell 206B-3 - License-built in Italy.
Bell 206L-3+ LongRanger - Bell modifications to upgrade aircraft to 206L-4 configuration.
Bell 206L-4 LongRanger IV - Improved version, 250-C30P engine and transmission upgrade.
Bell 206LT TwinRanger - Twin-engined conversions and new-builds of the 206L; replaced by the Bell 427.
Bell 407 - based on the 206L with four-bladed rotor system
Bell 417 - upgraded 407 with bigger engine; project cancelled.

Military

Bell 206L TexasRanger in 1981

Bell 206AS: Export version for the Chilean Navy.
OH-58 Kiowa: Light observation helicopter that replaced the OH-6A Cayuse.
TH-57A: 40 commercial Bell 206A aircraft purchased as the primary U.S. Navy helicopter trainer in January 1968, designated "Sea Ranger".[1]
206L TexasRanger: proposed export military version, only a demonstrator was built in 1981.
TH-57B: 45 commercial Bell 206B-3 helicopters purchased in 1989 as replacements for the TH-57A for primary training under visual flight rules.
TH-57C: 71 commercial Bell 206B-3 helicopters purchased beginning prior to 1985 with cockpits configured for advanced training under instrument flight rules.
TH-57D: Planned upgrade program to convert TH-57B and TH-57C to a single standard digital cockpit.[2]
TH-67 Creek: 137 commercial Bell 206B-3 purchased in 1993 as the primary helicopter trainer for the U.S. Army. 35 in VFR configuration and 102 in IFR configuration.[3]